c/mirror_zfs
1
0
Fork 0
mirror of https://git.proxmox.com/git/mirror_zfs.git synced 2026-05-24 11:18:52 +03:00
Code Issues Packages Projects Releases Wiki Activity

Prevent race in blkptr_verify against device removal

Browse Source 
When we check the vdev of the blkptr in zfs_blkptr_verify, we can run 
into a race condition where that vdev is temporarily unavailable. This 
happens when a device removal operation and the old vdev_t has been 
removed from the array, but the new indirect vdev has not yet been 
inserted.

We hold the spa_config_lock while doing our sensitive verification. 
To ensure that we don't deadlock, we only grab the lock if we don't 
have config_writer held. In addition, I had to const the tags of the 
refcounts and the spa_config_lock arguments.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #9112
This commit is contained in:
Paul Dagnelie
2019-08-13 20:24:43 -07:00
committed by Brian Behlendorf
parent 8e556c5ebc
commit dc04a8c757
5 changed files with 35 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files
module/zfs/spa_misc.c
+2 -2
View File
@@ -484,7 +484,7 @@ spa_config_tryenter(spa_t *spa, int locks, void *tag, krw_t rw)
}
void
spa_config_enter(spa_t *spa, int locks, void *tag, krw_t rw)
spa_config_enter(spa_t *spa, int locks, const void *tag, krw_t rw)
{
int wlocks_held = 0;
@@ -517,7 +517,7 @@ spa_config_enter(spa_t *spa, int locks, void *tag, krw_t rw)
}
void
spa_config_exit(spa_t *spa, int locks, void *tag)
spa_config_exit(spa_t *spa, int locks, const void *tag)
{
for (int i = SCL_LOCKS - 1; i >= 0; i--) {
spa_config_lock_t *scl = &spa->spa_config_lock[i];